The present invention relates to system and network management, and more particularly, to a method and system for consolidating management state information of one or more devices attached to or participating in a network, and sending the consolidated information to one or more management servers.
In computer network environments, it is advantageous to manage the various software and hardware components coupled to the network from a central location or from a remote location. Such central or remote management of a network is commonly accomplished using industry standard protocols, such as the Simple Network Management Protocol (SNMP) or the Desktop Management Interface (DMI). Traditional network discovery is performed in one of the several ways. One method is called explicit discovery, where the network address of the device is explicitly specified to the management software. Another traditional method is Internet Protocol (IP) pinging, where the management software enumerates a range of network addresses and individually pings the addresses to detect active devices. Yet another traditional method is performed using router tables, where the management software collects potential device addresses from network router tables.
In the case of explicit discovery, it is necessary to learn the address of each device and enter the value in the management software. This is a time consuming process in a network of any substantive size. Additionally, since many devices are dynamically assigned network addresses, the explicitly entered information may become invalid with the passage of time. IP pinging is time consuming, consumes network bandwidth, and may produce inconclusive results. Additionally, when the presence of the device is detected, no information as to what sort of device has been detected is available. The use of router tables is also subject to similar deficiencies as IP pinging. In all of these traditional cases, the fact that the address of a device can be dynamically changed is an ongoing problem. Once a device""s address is changed, the management software is no longer be able to communicate with it. These techniques rely on low level network protocols, and changes in network infrastructure technology often renders these traditional methods less effective or even non-effective.
Another requirement to managing devices attached to or otherwise participating in a network is to continuously monitor the state of those devices. One traditional method to monitor devices is to periodically poll the devices. Typically, a management server uses a management protocol, such as SNMP, to query each device to determine its state. On the basis of the response received from the device, an assessment of the state of the device is made. Several possible results are obtained from a device poll, including, but not limited to: 1) no response, where the device is either inoperative or network connectivity has been lost; 2) same response, where the device indicates that its state is the same as it was during the previous poll; 3) changed response, where the device indicates that its state is different than it was during the previous poll, such as, for example, degraded or upgraded, etc.
Continuous device polling generates an unacceptable amount of network traffic. Additionally, most of the polling traffic reveals that there is no change in the device state, so that the poll is wasted since it did not generate new information. To obtain and maintain device state information that is the most accurate, a system using traditional techniques would have to consume an unacceptable amount of the available network bandwidth. Additionally, another consideration in polling for device state information is the ability of the management computer system to support a high level of network traffic that would be required by polling. In a network with a large number of devices, the frequency of polling is constrained by the processing power and network bandwidth of the management computer system.
It is desired to provide a system and network management system with improved monitoring of devices attached to or otherwise participating in a network. It is desired to reduce network traffic related to management functions, such as monitoring, and to enable device information to remain updated regardless of network changes. It is desired to provide updated information about devices upon initialization and continuously or periodically during operation, rather then requiring continued extraneous communication and/or polling that would otherwise consume valuable network bandwidth.
A device that supports automatic state consolidation according to the present invention couples to a network subnet or otherwise participates in a network via the network subnet. The device includes a management database that stores local status information of the device and external status information from other, similar devices coupled to the network subnet. The device further includes beacon logic that periodically sends beacon packets onto the subnet, where each beacon packet includes the local status information from the management database. The device further includes monitor logic that stores external status information into the management database from beacon packets received from external devices sent via the subnet, and forward logic that periodically determines if it is master, and if it is master, that periodically forwards the local and external status information from the management database onto the subnet while it is master.
In this manner, each of a plurality of such devices coupled to a network subnet has a database with updated status information of all of the devices. The status information is periodically forwarded via the subnet to another device in the network, such as one or more management servers. The forward logic, if it determines that is master, forwards the local and external status information either periodically, if there is a change in the local and external status information, or a combination of both. In this manner, a management server is always apprised of the status of devices on the subnet.
The device may include one or more management agents that each collect the local status information and that stores the local status information into the management database. The device may further include registration logic that stores server information from a server beacon packet received from the network subnet and that forwards the server information to the subnet using a server beacon packet. The device may further include communication logic that operates with the beacon logic, the monitor logic and the forward logic to enable communication on the network subnet according to the HyperText Transfer Protocol (HTTP). The forward may forward the local and external status information via the communication logic in the form of an HTTP post transaction including an entity body. An HTTP tag or the like may be provided to identify the type of entity body, which may further include a Multipurpose Internet Mail Extension (MIME) descriptor or the like.
The local and external status information may include a plurality of beacon intervals, where one beacon interval is provided for each of the devices on the subnet. Each beacon interval may determine, for example, how often the corresponding beacon logic of a device sends beacon packets on the network subnet. The forward logic bases its determination of being master at least in part on comparisons of the plurality of beacon intervals. In one embodiment, for example, the device having the shortest beacon interval is determined to be master. Each device on a given subnet also has an unique address, such as an IP address or the like. In the event two or more devices have the same beacon interval, the forward logic further determines whether it is master on a comparison of a unique addresses. In any event, the criterion used to determine which device is master ensures that only one device is master at any given time.
The network may include two or more network subnets and one or more filter devices, such as routers or the like, coupled between respective network subnets. The beacon packets may be broadcast packets that are filtered by the filter device so that the beacon packets are not transferred to other subnets. For example, each subnet may include a separate group of devices, where the beacon packets from each group are isolated from the beacon packets of other groups. This reduces the amount of network traffic on the network as a whole. When forwarding consolidated status information comprising the local and external status information to a management server, the forward logic may send a unicast packet via a network subnet. The unicast packet includes an address for a particular device in the network, such as a management server, where the filter devices relay the unicast packet to the appropriate subnet to which the management server is coupled.
A method of consolidating status information of a plurality of devices coupled to a first network subnet and for sending consolidated information to a management server according to the present invention comprises steps of periodically sending, by each of the plurality of devices, status information to the other of the plurality of devices on the first network subnet, receiving and storing, by each of the plurality of devices, status information received from the other of the plurality of devices, selecting one of the plurality of devices as master, and periodically sending, by the selected master, consolidated status information of the plurality of devices in a consolidated form to the management server. The consolidated status information forwarded to the master may be sent periodically, or may be sent if a change occurs in the consolidated status information, or may be sent according to a combination of a predetermined period and whether there is a status change. The selecting of a master may comprise determining, by each of the plurality of devices, whether it is master based on a common selection criterion that ensures only one master.
The method may further comprise steps of receiving, by one of the plurality of devices, server information from the management server, and forwarding the server information to the other of the plurality of devices on the first network subnet. In this manner, all of the devices on the subnet or part of the same group, have the server information, so that any device that can serve as master may locate the management server. Of course, more than one management server may register, so that all devices have the server information of all management servers that have registered.
It is appreciated that automatic state consolidation for network participating devices according to the present invention provides a network management system with improved monitoring of devices attached to or otherwise participating in a network. Automatic state consolidation reduces network traffic related to management functions, such as monitoring, and enables device information to remain updated regardless of network changes. Automatic state consolidation provides updated information about devices upon initialization and periodically during operation, rather then requiring continued extraneous communication and/or polling that would otherwise consume valuable network bandwidth.